In general, a fan for supplying heat exchangers, such as a radiator and a condenser, with a cooling air is supported by a fan shroud. For example, Japanese Unexamined Patent Application Publication No. 11-171041 describes a fan shroud integrally having an air cleaner housing.
The described fan shroud form recess parts at an upper portion thereof as the air cleaner housing. Each of the recess parts is open to a rear side of the fan shroud. An air cleaner element for removing fine particles such as dust from air is arranged in the recess part, and a rear opening of the recess part is covered by a cover member. As such, an air cleaner unit is integrated into the fan shroud. The described fan shroud also has inlet openings for introducing air into the recess parts on its front wall. The cover members have outlet openings for discharging the air, which has been cleaned through the air cleaner element, from the air cleaner housing.
In such an air cleaner unit, the inside space provided by the recess part is almost occupied by the air cleaner element. Therefore, the resistance to flow of the air from the inlet openings to the outlet openings through the air cleaner element is likely to increase. The increase in the resistance to flow of the air results in a decrease in the amount of intake air to be introduced to an engine of a vehicle and deterioration of engine power. Also, if rain and snow are introduced in the air cleaner unit with the air, the rain and snow are accumulated in the inside space, and thus the air cleaner element will be soaked.